It is the purpose of the proposed research to determine the electrical parameters required for optimum epiphyseal plate stimulation and to determine the mechanism of action of such an electrical field on ephiphyseal plate chondrocytes. In Vitro epiphyseal plate growth will be determined in various pulsed magnetic fields (inductive coupling) and in various electrical fields (capacity coupling). Cytoplasmic components of the electrically stimulated growth plate will be compared quantitatively with cytoplasmic components of the control growth plate. Cyclic-AMP, hexosamine, hydroxyproline, and tritiated thymidine will be determined in dissociated growth plate chondrocytes grown in various pulsed magnetic and electrical fields.